1. Field of the Invention
The apparatus of the present invention relates generally to bins for storing articles, and more specifically to an intelligent bin in which the stored articles can be identified during a manufacturing process such as the manufacturing of semiconductors.
2. Description of the Prior Art
Semiconductor wafers are typically processed in batches of twenty five or fifty. These wafers are held in cassettes in groups of twenty five between processing steps. In order to maintain cleanliness, these cassettes may be placed in a cassette box. These cassette boxes are typically made of plastic, and may have latches to close the lid. The cassette boxes may also hold one or two cassettes.
A major problem in the manufacturing of integrated circuits or semiconductor wafers is the lack of knowledge concerning position of inventory in the manufacturing process. Typically, a piece of paper is taped to a cassette box with the identity and progress through the process indicated on the paper. However, the actual physical position of the cassette box is unknown. The box may be on a table, or in a rack, or stacked on the floor. If it is needed, a person is required to go and look for the box. It is possible that several hundred boxes are in process at the same time, thus positive control and location identification are missing.
Accordingly, there is a need for an intelligent bin which can identify an article such as a cassette box and provide an indication of its location.